A Comparative Study on the Effects of Sequential and Concurrent Engineering on Design Efficiency

Purpose: This study aims to empirically examine the effectiveness of concurrent engineering design (CED) as an alternative to traditional sequential engineering design (SED), which is widely applied in small and medium-sized manufacturing enterprises (SMEs). The linear procedure of SED imposes limitations on interdepartmental collaboration and delays in information transfer, thereby increasing the frequency of rework and design errors. These constraints ultimately reduce the overall efficiency of engineering projects.Methods: This study analyzed 1,151 cases of non-standard product design based on actual design data collected from a small and medium-sized manufacturing enterprise. We identify design time, design cost, and redesign rate as the key performance indicators. In particular, each performance indicator was maintained independently without integrating them into a single composite metric, in order to prevent analytical distortions that could arise from unit inconsistencies, nonlinear correlations, and variability in the importance of each indicator within the actual design environment.Results: The analysis revealed that the CED approach reduced design time by an average of 30.33% compared to SED. In addition, the rework rate was significantly lower in CED across all major design stages, including detailed design, drawing review, and document control. Improvements were also observed in schedule predictability and design quality stability. These advantages are interpreted as results of parallel design processes that enable real-time feedback and interdepartmental collaboration.Conclusion: This study empirically demonstrates that concurrent engineering design not only shortens design lead time but also enhances quality and schedule reliability. The findings are grounded in real-world data obtained from an SME and offer a practical theoretical basis for considering CED as a strategic design methodology in the small-scale manufacturing sector.